Rotary piston engine



Sept. 12, 1967 E. A. LINK ROTARY PISTON ENGINE 2 Sheets-Sheet 1 Filed April 1, 1965 INVENTOR. EDWIN A. LINK RONALD E. BARRY 7 ATTORNEY Sept. 12, 1967 E. A LINK 3, 3

' ROTARY PISTON ENGINE Filed April 1, 1965 2 Sheets-Sheet 2 INVENTOR. EDWIN A. LINK RONALD E. BARRY ATTORNEY I u United States Patent Office 3,340,853 Patented Sept. 12, 1967- 3,340,853 ROTARY PISTON ENGINE Edwin A. Link, 317 S. Greenfield Ave., Waukesha, Wis. 53186 Filed Apr. 1, 1965, Ser. No. 444,559 12 Claims. (Cl. 123-8) This invention relates in general to rotary piston type apparatus such as an engine or a pump and more particularly to a combination rotor and stator wherein the stator has one more chamber than there are lobes on the rotors.

In apparatus of this type, the rotor is positioned within a stator and rotates about an axis which is offset from the rotating axis of a crank shaft. The direct-ion of rotation of the rotor is opposite to the direction of rotation of the crank shaft. This type of apparatus has not met with much success for a number of reasons. This is caused to some extent by the high degree of wear which occurs between the rotor and the walls of the stator. This type of apparatus also requires complicated valving in order to control the admission and exhaustion of gases from the chamber in the stator.

One of the principal objects of the present invention is to provide an improved rotary piston apparatus in which additional inlet and outlet valves are eliminated.

Another object of the present invention is to provide an improved rotary piston apparatus which is subject to substantially little wear between the rotor and stator.

Another object of the present invention is to provide an improved rotary piston apparatus in which a positive seal is provided between the rotor and piston.

Still another object of the present invention is to provide an improved rotary piston apparatus which can be adapted for use as a pump or an internal combustion engine.

A still further object of the present invention is to provide an improved rotary piston type engine in which the rotor and stator are dynamically balanced.

These objects are accomplished by positioning a two lobe rotor within a stator which has one more chambers than there are lobes on the rotor. The rotor is amounted to rotate on an axis which is offset from the axis of the crank shaft of the apparatus with the axis of the rotor rotating in a direction about the axis of the crank shaft opposite to the direction of rotation of the rotor. The contour of the lobes of the rotor is substantially the same as the contour of the chambers so that the rotor lobes will move easily into and out of the chambers. As each lobe on the rotor enters a chamber, a compression stroke is produced and as it leaves, an expansion or suction stroke is produced.

The rotor is provided with at least two passages in one of the lobes with one of the passages connected to an inlet passage in the crank shaft and the other connected to an exhaust passage in the stator. Each of the passages terminates on substantially diametrically opposite sides of the surface of one of the lobes of the rotor in a position to be sealed by the walls of the stator as the rotor is moved about the chambers in the rotor. One of the walls in each of the chambers of the stator is slotted to allow for a limited amount of flexibility in a section of the wall which is in contact with the walls of the rotor. The section is actuated to form a positive seal with the rotor by the buildup of pressure within the chamber as well as in the slot to move the flexible section against the wall of the rotor. The flexibility of the wall of the chamber insures a good seal between the rotor and the stator when the chamber is under pressure and also allows for freedom of motion between the rotor and stator when the pressure is released, reducing the amount of wear caused by friction between the rotor and stator.

The combination of the rotor and stator, as briefly described above, is used as an internal combustion engine and can be modified for use as a hydraulic motor or pump by adding inlet and outlet passages to the other.

lobe of the rotor which are also in communication with the inlet and exhaust passages in the stator. When this combination of rotor and stator is used as an internal combustion engine, inlet and outlet passages are provided in one lobe and an ignition device such as a glow plug or spark plug is positioned to cooperate with the other lobe. When the non-vented lobe enters a chamber, the fuel-air mixture is compressed and on ignition an expansion stroke is produced. When the lobe having the inlet and outlet passages enters and leaves a chamber, the combustion products will be exhausted on the inlet stroke and on the outward stroke, the combustion products will be drawn into the chamber.

When the rotor and stator are used as a pump, inlet and outlet passages are provided in both lobes. Each lobe will then act independently. On the incoming stroke, the gas or fluid in the chamber will be forced out and on the outgoing stroke, the gas or fluid will be drawn into the chamber. It is also within the teachings of this application to hold the crank shaft stationary and to rotate both the rotor and housing about the crank shaft. With this arrangement, the engine or pump will be dynamically balanced at all times.

In the above description, a two lobe rotor and three chamber stator were described but any number of lobes can be provided on the rotor depending on whether it is to be used as an engine or pump with a stator having one more chamber than there are lobes on the rotor. Other objects and advantages will become more readily apparent from the following detailed description when read in connection with the accompanying drawings, in which:

FIG. 1 is a view of the apparatus partly in section, showing the relative position of the rotor within the stator.

FIG. 2 is a side view in section of the rotor and stator showing the inlet and outlet chamber.

FIG. 3 is a section view of the rotor and stator, showing the position of the rotor immediately after ignition.

FIG. 4 is a view of the rotor and stator showing the position of the rotor with the crank turned through FIG. 5 shows the position of the rotor with the crank turned through 300.

FIG. 6 is a view of the rotor and stator showing the crank turned through 540.

FIG. 7 shows the crank turned through 600.

FIG. 8 shows the crank turned through 660.

FIG. 9 shows a sectional view of a rotor and stator used as a pump.

FIG. 10 is a side view of a rotor and housing mounted on a stationary crank shaft.

FIG. 11 is a front sectional view of the rotor and housing shown in FIG. 10.

FIG. 12 is a view of a three lobe-four chamber arrangement for the rotor and housing.

In FIGS. 1 and 2 a stator 10 is shown having side wall plates 12 and 14 secured to a central member 16 by any appropriate means, such as bolts 18. The central member is slotted to form working chambers 20, 22 and 24 which are closed on the sides by the side wall plates. One of the walls of each of the chambers has a slot 26, 28 and 30 cut at a slight curve to isolate wall sections 32, 34 and 36 in each of the chambers.

A rotor 38 is positioned to rotate within the chambers of the central member and has two lobes 40 and 42 which have substantially the same radius of curvature as the radius of curvature of each of the chambers. Lobe 42 has an exhaust passage 44 and an inlet passage 46 which terminate in ports or slots 48 and 50, respectively,

in the side walls of the lobe of the rotor. The lobes have circular curvatures with the slots located on substantially diametrically opposite points of the lobe equidistant from the top dead center point of the lobe. Referring to FIGS. 4 and 6 it will be noted that when lobe 42 is axially aligned with one of the chambers, the top or end of the lobe will be spaced from the wall of the chamber and both slots will almost be closed by the side walls of the chamber. When the lobe is moved out of axial alignment with the chamber, one or the other of said passages will be opened into the chamber.

The exhaust passage is connected to an exhaust recess 52 in the center of one side of the rotor and the inlet pass-age is connected to an inlet recess 54 located on the other side of the rotor. When the rotor is positioned in the stator the exhaust recess will always be in communication with exhaust outlet 56 in plate 12 and the inlet recess will always be in communication with a passage 58 in crank shaft 60. The crank shaft is journalled in bearing 59 of any suitable type which also seals the combustible products in the passages.

The rotor is mounted to rotate on a pin 62 which is secured to crank shaft 64 but offset from the rotational axis of the crank shaft. In FIG. 1 it will be noted that the rotor rotates in a counter clockwise direction while the crank shaft rotates in a clockwise direction. The passage 58 in the crank shaft is always in communication with the inlet recess and is connected to a carburetor 61 of any appropriate type through passages 63 and '65 for drawing combustible gases into the chamber.

A glow plug 66 is shown in the head of lobe 40- to ignite the combustible products which have been compressed in the chamber whenever the compression ratio of the products within the chamber reaches the ignition point. A spark plug type ignition system could also be used in place of a glow plug as described in connection with FIGS. 10 and 11 or self-ignition system could be used if a high compression ratio is used.

In order to better understand the operation of the device, reference will now be made to FIGS. 3 through 8 which show a full cycle of operation for one revolution of the rotor.

In 'FIG. 3 the pin 6-2 on shaft 60 is shown at what will be considered a starting point. Rotor lobes 40 and 42 are positioned in chambers 20 and 22, respectively, and ignition has just occurred in chamber 20. The rotor will move in the direction of the arrow shown in chamber 24, pushing the pin clockwise as shown by the arrow on the rotor. As lobe 40 enters chamber 24 (FIG. 4) it will compress the fuel-air mixture which is present in the chamber. The combustion products in chamber 20 will still be under pressure as a result of the ignition which occurred in FIG. 3. As lobe 42 enters chamber 20 (FIGS. 4 and 5) the exhaust port or slot 48 will be opened into the chamber, allowing the combustion products to exhaust through port or slot 48 into passage 44, exhaust recess 52 and out through exhaust outlet 56. At the same time chamber 22 will fill with a fresh mixture of air and gas since port or slot 50 will be opened into chamber 22. As lobe 40 enters chamber 24, it will compress the fuelair mixture present in chamber 24 and as it approaches dead center in the chamber ignition will occur, forcing lobe 40 out of chamber 24 toward chamber 22. As lobe '40 rotates in chamber 20, as a result of lobe 40 moving toward chamber 22, exhaust port or slot 48 will come into contact with the wall of chamber 20, sealing it from the chamber. At approximately the same time the inlet port or slot 50 will be opened in the chamber and as lobe 42 is drawn out of chamber 20 a vacuum will be created, drawing fuel-air mixture through the inlet passages 58, 54, 46 and port or slot 50 into the chamber. This sequence of events will be repeated in each of the chambers as lobe 42 enters and leaves the ch mber nd a l be 40 4 enters and compresses the fuel-air mixture which is ignited as the lobe reaches dead center in the chamber.

The rotor is sealed against the side walls of the chamber by the flexibility provided in sections 32, 34 and 36. Referring again to FIG. 1, it will be noted that when ignition occurs in one of the chambers, considerable pressure is built up in that chamber. The slot which is in communication with that chamber will also be subjected to the same pressure. The increase in pressure behind the corresponding section will force the section against the side wall of the lobe. This squeezing action will seat the rotor tightly between the side walls of the chamber, preventing any escape of the combustion products into the adjacent chambers.

In FIG. 9 a sectional view of a rotor 70* and stator is shown wherein the combination is used as a pump. The stator includes a central member 88 enclosed by side plates as described above with crank shaft 72 mounted for rotary motion in one of the side plates. The crank shaft can be driven by any appropriate means to rotate offset pin 74 in a concentric circle about the axis of the crank shaft. Rotor 70 is mounted on the pin for rotary motion within the central member of the stator with the lobes 76 and 78 being alternately moved into and out of chambers 82, 84 and 86 in the central member.

In order to achieve a pumping action, both lobes 76 and 78 are provided with inlet passages 90 and exhaust passages 92. These passages terminate in corresponding inlet ports or slots and outlet ports or slots located on diametrically opposite sides of the rotor lobes as described above. An inlet recess is provided in the crank shaft side of the rotor which is in constant communication with a passage in the crank shaft. An outlet recess is provided on the other side of the rotor and is always in communication with an outlet passage in the side plate of the stator. The gas or fluid which is pumped through the rotor is admitted through passage 90 and will be forced out through passage 92. The side wall slots 21, 23 and 25 may be provided to improve the seals along the side walls as well as reduced wear.

In operating the pump, the crank shaft is rotated in a clockwise direction in FIG. 9. As lobe 76 enters chamber 82 any fluid within the chamber will be compressed and forced out through exhaust passage 12. When the lobe passes dead center, the exhaust port or slot will be closed by the side wall of chamber 82 and the inlet port or slot will be opened. As the lobe is drawn out of the chamber, a vacuum will be created in the chamber, drawing gas or fluid through the inlet passage 90. This cycle is repeated each time a rotor lobe is moved into or out of one of the chambers. If the pump is driven as a hydraulic motor, the flow of fluid is reversed through the passages so that the incoming fluid is pressurized on one chamber to rotate the rotor.

In FIG. 10 a rotor and housing 102 are shown which are both mounted for rotary motion on a stationary shaft 104. The housing includes a central member 106 having side plates 108 and 110 with the shaft journalled in appropriate hearings in side plate 108. A drive gear or sheave 112 is secured to the outside of side wall 110 and is connected by a chain or belt to the device which is to be driven by the engine. The central member is slotted as above to form working chambers 114, 116 and 118.

The rotor is mounted for rotation on pin 120 which is offset from the axis of the crank shaft and rotates about the pin in the same direction of rotation as the housing rotates about the shaft. An exhaust passage 121 and an inlet passage 122 are provided in lobe 124 of the rotor and terminate in ports or slots 126 and 128, respectively. An ignitor may be provided in lobe 130' or an ignition system as shown in FIG. 10. In an internal combustion engine of this type, ignition will occur as each alternate chamber passes top dead center. Since the chambers will either be filled with compressed fuel-air mixture or exhausted when they pass top dead center, the ignitor is energized each time a cylinder passes top dead center. The ignition circuit shown includes a spark plug 140 in each chamber with a contact circuit 142 positioned to engage a spark plug each time it passes the contact circuit. The contact circuit is connected to coil 154 which is energized by battery 155 through coil 152. Cams 144 are provided on the housing to close contacts 146 and 148 in circuit 150 to energize circuit 142 through coils 152 and 154 each time a spark plug passes circuit 142.

In operation, assuming that lobe 130 is completely in chamber 116 and the fuel-air mixture is completely compressed, the spark plug is energized, causing an explosion in the chamber. The housing will be driven in a clockwise direction, carrying the rotor in the same direction. Lobe 124 will be forced into chamber 114, compressing the gas in chamber 114 and forcing it out through the exhaust passage 121. As chamber 114 passes top dead center, lobe 124 will be drawn out of the chamber, creating a vacuum and drawing fuel-air mixture into the chamber through inlet passage 122. Lobe 130 will start to enter chamber 118, compressing the fuel-air mixture present in the chamber. When chamber 118 passes top dead center, the spark plug will be energized, starting a new cycle of operation. It should be noted that for each complete revolution of the rotor, the housing will revolve two-thirds of a revolution. Since the rotor and housing are both rotating on their own stationary axes, they will be in dynamic balance at all times.

In the various descriptions of the rotor and stator or housing combination, the rotor has always been described as mounted on a pin secured'to the crank shaft. The rotor can be connected to the crank shaft in other ways, such as through a gearing arrangement, particularly in the stationary shaft type engine as described in FIGS. and 11. The relationship of the crank shaft, housing and rotor in the application is similar in some respects to the operation of a planetary gear arrangement. One of the three members, the housing or crank shaft, is held stationary while the forces set up in the rotor are used to rotate the others. In a planetary gear, the ring or sun gear is held stationary and the force imparted to the planetary gears is transferred to the other.

The rotor and stator combinations shown and described have all been of the two lobe-three chamber type. It is possible to increase the number of lobes on the rotor and to provide one more chamber in the housing than there are lobes on the rotor. As seen in FIG. 12 a rotor 160 having three lobes 162 is mounted to rotate on pin 164 on crank shaft 166. The rotor is positioned within housing 168 which has four chambers 170. Inlet vents 172 andoutlet vents 174 are shown in all three lobes of the rotor so that it can be driven as a pump. The operation of this type rotor-stator combination will be substantially as described above.

Although only a few embodiments of the present invention have been shown and described, it should be apparent that various changes and modifications can be made therein without departing from the scope of the appended claims.

What is claimed is:

1. A rotary piston device comprising a housing member having a number of identically shaped chambers,

each of said chambers having sidewalls and parallel planar endwalls located a predetermined distance apart,

a rotor having a number of lobes equal to one less than the number of chambers,

each of said lobes having planar endwalls,

at least one of said lobes having inlet and exhaust passages,

said inlet passage extending through said rotor from a port substantially at the central axis of one of said endwalls of said housing to a port on one sidewall of said lobe,

said exhaust passage extending through said rotor from a port substantially at the central axis of the opposite endwall of said housing to a port on the sidewall of said lobe substantially opposite said inlet port,

a shaft journalled in the central axis of said housing,

said rotor being drivingly connected to said shaft whereby said rotor moves a planetary type motion with respect to said housing and shaft,

said planar endwalls and said sidewalls of each of said lobes sealingly engaging the corresponding Walls of said chambers as each moves into and out of the chambers.

2. A rotary piston device according to claim 1 wherein said housing member has an odd number of chambers equal to N, and said rotor has N1 lobes, said device including means for imparting rotary motion to said rotor comprising a source of combustible fluid mixture operatively connected to said inlet passage.

an ignition device for igniting a combustible mixture admitted to the chambers through the inlet passage when a non-vented lobe enters the chamber.

3. A rotary piston device according to claim 1 including a power source connected to rotate the shaft thereby driving the rotor into and out of said chambers.

4. A rotary piston device according to claim 1 including pressure means for forcing a fluid through the inlet passages in the lobes of the rotor to thereby impart relative motion between said rotor, housing member and shaft.

5. A rotary piston device according to claim 1 wherein said housing includes flexible sections in the corresponding sidewall surfaces of each of the chambers which are responsive to an increase in pressure in the chamber to sealingly engage the side walls of the lobe within the chamber.

6. A rotary combustion engine comprising, in combination,

a rotor having an even number of lobes with at least one of said lobes including an inlet passage for a fuel-air mixture and an exhaust passage for exhausting products of combustion, said passages terminating on the sidewalls of said lobes,

a housing having a number of chambers equal to one more than the'number of lobes on the rotor, and

a drive shaft journalled in the center of the housing and being mechanically interlinked with said rotor to move said rotor in a planetary manner in said housing, an ignition means in each of said chambers and a source of fuel-air mixture connected to said inlet passage whereby on ignition of said fuel-air mixture said rotor lobes will move out of said chambers.

7. A rotary combustion engine according to claim 6 wherein said housing includes a flexible station along one wall of each of said chambers, said section of sidewall being flexible to maintain a seal between the rotor lobes and chamber housing.

8. The combination of a rotor and housing for a rotary device, comprising a housing having a number, n, of working chambers equally spaced around its geometric axis, each of said chambers having parallel sidewall sections,

a drive shaft journalled in said housing for rotary motion and having an eccentric section connected to said shaft at a point offset from the axis of rotation of said shaft,

a rotor having n-l number of lobes, said rotor including an inlet passage and an outlet passage in at least one of said lobes each of said lobes having cylindrical sidewall surface portions which engage the sidewall sections of said chamber to provide a seal as the lobes move into and out of said chambers, said rotor being drivingly connected to the eccentric section of said shaft whereby said rotor, housing and shaft can move relative to each other in a a passage in said shaft connected to one of said pasplanetary manner. sages in said inner body, and p 9. The combination of a rotor and housing according a passage in the wall of said outer body connected to claim 8 wherein said inlet and outlet passages terto the other of said passages in said inner body, minate on substantially diametrically opposite sides of whereby on rotation of said inner body within said said lobes. outer body, fuel-air mixture will be drawn through 10. An internal combustion engine, comprising, a housing having an odd number of chambers, each of said chambers having planar sidewall sections spaced said shaft and combustion products will be exhausted through said opening in the other end wall, a source of fuel-air mixture, ignition means in each of said a predetermined distance apart, 10 chambers for igniting the compressed fuel-air mixa shaft journalled in said housing at its geometric axis ture admitted to the chambers through the passages.

for rotary motion, 12. A rotary piston device comprising a rotor drivingly connected to said shaft to provide a housing having a number of chambers equally planetary type motion between said shaft, rotor spaced about its central axis, each of said chambers and housing, having parallel planar sidewall sections located a said rotor having an even number of lobes equal to p edetermined distance apart,

one less than the number of hambe s in the housin a rotor having a number of lobes equally spaced about each of Said lobes having a cylindrical sidewall its center axis, the number of said lobes being equal portion and having a diameter substantially equal to ne less than t number f chambers in the to the distance between the planar sidewall sections g, each of Said lobes having Planar sidewalls, of said chambers, whereby each chamber is sealed at least one of said lobes havin all inlet and an by the engagement of the sidewalls of the lobe with ou let passage, said passages each having one end the sidewall sections of the chambers as the lobes terminating 0n 'appfoXilTlateiy diametrically pp enter and leave the chambers, sides of the sidewalls of said lobe and the other a source of fuel air mixture, end on the end wall of the said rotor, said housing ignition means in each chamber of said housing, said including inlet and Outlet Passages Positioned for rotor having inlet and outlet passages i t l t continuous communication with the other ends of one of said lobes which terminate near the cylindrithe inlet and outlet passages in the rotor, said rotor cal sidewall of said lobe at substantially diametrilobes sealingly engaging the sidewall sections of cally opposite points, said housing having inlet and 0 said housing to divide the housing into separate exhaust passages which are in constant communicachambers, U011 with the ini'et Passage to Said fuel air Source a drive shaft journalled for rotation on the central axis and outlet passage for exhausting burnt gases, reof id hou ing, p iy i y imparting inqtion to said i said rotor being drivingly connected to said shaft for 3 58 3 f g i W111 be drawn ,g the housmg rotation within said housing about an axis spaced chamgmrs a1nd in e passages as Sa lobe leaves a from the rotational axis of said shaft. exhaust products will be expelled from said housin through said exhaust passages as said lobe enter? References Clted a chamber. UNITED STATES PATENTS rotary mechalilm comprising 211,5 1 1g7 Nash a pair of parallel axially spaced end walls, 2 923 9 2 19 0 Lorenz 103 126 a peripheral wall interconnecting the end walls, said 6/1961 Q TIIII peripheral wall separating the space between the 3115871 12/1963 L k 91 68 end walls into an odd number of chambers, 3253583 5/1966 a shaft journalled for rotation in one of said end Su agawa 123 8 i b d t d d h ft f 1 t FOREIGN PATENTS an inner o y moun e on sai s a or p ane ary type motion with respect to said housing and shaft, 6/1964 France said inner body having an exhaust passage and an 176112 2/1922 Great Bntam' inlet passage, one end of each of said passages 964O83 7/1964 Great Britainterminating on the outer surface of the walls of the inner body, the other end of said passages terminating on opposite sides of the center portion of said inner body,

ROBERT M. WALKER, Primary Examiner.

WILBUR J. GOODLIN, Examiner. 

1. A ROTARY PISTON DEVICE COMPRISING A HOUSING MEMBER HAVING A NUMBER OF IDENTICALLY SHAPED CHAMBERS, EACH OF SAID CHAMBERS HAVING SIDEWALLS AND PARALLEL PLANAR ENDWALLS LOCATED A PREDETERMINED DISTANCE APART, A ROTOR HAVING A NUMBER OF LOBES EQUAL TO ONE LESS THAN THE NUMBER OF CHAMBERS, EACH OF SAID LOBES HAVING PLANAR ENDWALLS, AT LEAST ONE OF SAID LOBES HAVING INLET AND EXHAUST PASSAGES, SAID INLET PASSAGE EXTENDING THROUGH SAID ROTOR FROM A PORT SUBSTANTIALLY AT THE CENTRAL AXIS OF ONE OF SAID ENDWALLS OF SAID HOUSING TO A PORT ON ONE SIDEWALL OF SAID LOBE, SAID EXHAUST PASSAGE EXTENDING THROUGH SAID ROTOR FROM A PORT SUBSTANTIALLY AT THE CENTRAL AXIS OF THE OPPOSITE ENDWALL OF SAID HOUSING TO A PORT ON THE SIDEWALL OF SAID LOBE SUBSTANTIALLY OPPOSITE SAID INLET PORT, A SHAFT JOURNALLED IN THE CENTRAL AXIS OF SAID HOUSING, SAID ROTOR BEING DRIVINGLY CONNECTED TO SAID SHAFT WHEREBY SAID ROTOR MOVES A PLANETARY TYPE MOTION WITH RESPECT TO SAID HOUSING AND SHAFT, SAID PLANAR ENDWALLS AND SAID SIDEWALLS OF EACH OF SAID LOBES SEALINGLY ENGAGING THE CORRESPONDING WALLS OF SAID CHAMBERS AS EACH MOVES INTO AND OUT OF THE CHAMBERS. 